Trying to setup Kasa smart plugs and my nighthawk modem kicks off all wifi to my house

I have the nighthawk model RAX35.   I just obtained some Kasa Smart WIFI Plug Lite HS103's.  When I try to set them up to my internet so they can be used my wifi goes down.  The Modem disconnects all wifi and will not turn it back on.  I have to unplug the Kasa Smart plug to get it to start my wifi back up.  Something is going on between the modem and the Kasa smart plugs.  I tried working with Kasa but they said it is not on their end.  That it is on the Netgears modem end.   Which stinks for me becuase I am a few months out of warranty to get support.  Which makes it almost cheaper to go out and by a whole new modem instead perhaps not a netgear one at that.   I am wondering before I do all that if anyone has had similar issues and had them resolved?  Or would know why this occurs.  I have set up another brand of smart plug and it works fine along with other wifi items I use but for some reason the kasa ones disagree with my modem.  Thank you for any help.

Firmware version by the way for my modem is v1.0.3.62_1.0.1